More aileron work

With a week or so off in there due to both my wife and I having COVID, things have been progressing. I got one of the torque tubes measured and cut for the wing. The plywood bits for the nose of the aileron ribs all got drilled out. Looking at how to do the aileron build brought up some issues, though. The plans say to glue and clamp those in place — the challenge is in how to do that, exactly. The clamping anyway.

In order to make the job a bit less complicated, I glued up the plywood sandwiches for the two ends and the middle, where the locking pins will install. I spread some epoxy and threaded the pieces onto the cutoff piece of torque tube to get them all perfectly aligned – and they were tight. With everything aligned perfectly, I shot a few 1/2″ 23 ga. micro pins to keep everything stable, then added spring clamps and took them off the tube so they wouldn’t end up glued to it.

Next day I ran those and the 1/8″ ply pieces on a spindle sander with a 3/4″ drum on it to enlarge the holes a bit. I wanted a slip fit on the tube for the thicker pieces, and a more “roomy” fit for the 1/8″ pieces. Those were supposed to get 1-1/8″ holes in the first place, but I missed that part in the instructions and we drilled them to 1″.

Realizing that the wing now can’t sit flat on the steel rail due to the trailing edge of the wingtip bow not being tapered to match the wing, I took care of that as well. Only the last couple inches of the bow need to be tapered. I started with a little razor plane that Dad used for model airplane work to shave the bow lamination and corner block down very close to the contour I wanted. I then finished it up with a sanding block, and I’m quite happy with the result.

Everything is ready now to get the plywood pieces glued into place. I’d have done it today, but as I was about to mix up the glue I was reminded that it was time to go pick up the grandkids, which turned into dinner and a late arrival home.

Aileron and wingtip 12/2

Today we got the ends of the wingtip bows trimmed to length, and the wingtip supports trimmed to fit. I want to get the bows routed or sanded to their final shape before gluing them in, so that’s going g to need to wait a bit. I did cut the corner blocks for both ends.

The CW36 aileron bay end plates aren’t as bad as I thought, and the holes can be modified as needed, so I glued them in place. I also cut and glued in the remaining aileron spar stiffeners and the plywood piece that will hold the bracket for the aileron connecting rod. I think that’s everything I feel comfortable doing before getting the torque type in place. I also need to stop at Lowe’s Aviation Department to pick up a little chunk of 1” PVC pipe. The Celebrity uses 3/8” slices of plastic pipe to keep the ailerons centered in the aileron bays.

I was pretty chuffed. I estimated it would take about 8 cc of glue for everything I wanted to glue today… so I mixed up 8 cc, and ended up with almost nothing left over.

More left wing work

I’ve been over working on the wing a couple of times since the last post. Stu and I worked out what seems to be the best way to fit the wingtip bow. Yesterday we glued, stapled, and clamped the leading edge plywood to the top of the ribs and the top false spar, but left it at that stage. Wrapping the ply around the leading edge results in the upper edge pulling loose, so we decided to leave it as is and do the rest later on. I was planning on today, but may hold off on that until the wingtip bow is installed — I want to get the corner blocking glued in behind the LE ply, and that may be difficult with the plywood fully wrapped. Don’t know, I’ll need to look at that today.

We spent an hour or two yesterday trying to work out the aileron bits and pieces. The factory cut and drilled plywood bits (CW32, CW34, CW35, etc.) have been both a blessing and a curse. Most of the confusion seems to come from the fact that the CW36 pieces, which attach to the ribs just inboard and just outboard of the aileron bay, are apparently drilled WAY off. The pieces are too long for the wing to begin with — they seem to be sized for a rear spar built with the original 1/2″ thickness. non the current 3/4″. Then there’s a hole marked “more or less” on center, but the actual hole is drilled about 1/8″ or so low, or high, depending on how the piece is flipped. There is no orientation we could find that matches up with the holes drilled in the CW35 pieces that are used to attach the aileron to the torque tube. Fortunately, it really doesn’t matter. I’ll be cutting 1/2″ UHMW end bearings that will attach to those plywood pieces, so we can enlarge those holes as much as needed as long as there’s enough room left to attach the bearing pieces.

What we did get done was to cut and glue in the aileron spar web, and some of the 1/4″ stiffeners before the glue left over from the leading edge ply got too thick to work with. I glued up a test piece with that; the epoxy is a bit thicker than I would normally use, but I may have just been too conservative on that. I can’t think of any reason it wouldn’t give a full strength joint; the test piece will tell me for sure.

For the most part, I’m waiting for my aluminum for the torque tubes to arrive at Millard Metals, and sheets of 1/16 and 1/8 ply to arrive from Spruce. I need the ply to cut gussets for the compression struts, and we don’t want to get much farther into the ailerons without full length torque tubes to keep everything perfectly aligned.

Lower left wing, Day 5

After a couple days’ hiatus for Thanksgiving, I went over yesterday to resume work on the wing. We cut the notches in the nose ribs and got them glued in place, and I cut and glued the corner blocking for the four compression struts. I still need to cut and glue in the gussets for those. We took a look at some of the aileron pieces to figure out how all of that goes together. I’m waiting on a response from Millard Metals on my aileron torque tube stock; I don’t think we can do much until I have that. I think the next step will be to get the wingtip bow figured out, and wrap the leading edge with plywood. Then I could also start cutting and installing the bushings for all of the attachment bolts.

Lower left wing, Day 4

Last night I got the compression struts and the bottom geodetic bracing glued in. Next up will be gluing the various plywood pieces surrounding and supporting the ailerons. I got those out last night to see how they fit, and everything looks good so far. Waiting to hear back from the metal supplier on the 1″ diameter tubing I need for the ailerons.